In a portable electronic device called a smartphone or a tablet terminal, a display device, which forms a display screen, is a principal member as a member that occupies one surface of its main body. The main body of the portable electronic device has been requested to be thinned from an aesthetic viewpoint presented by its appearance. To satisfy such a request, the display device itself needs to be thinned.
A liquid crystal display known as one of display devices has a configuration in which a liquid crystal layer is provided between an element substrate provided with a pixel array using a transistor and an opposite substrate provided with a color filter. As one of means for thinning the display device, the element substrate using glass or the like also used for the opposite substrate has been thinned by mechanical polishing or chemical polishing. For example,
Japanese Patent Application Laid-Open No. 2009-294602 discloses a manufacturing method for sticking an opposite substrate cured by applying resin to a support substrate and an element substrate using a material such as glass together and thinning the element substrate by etching when the opposite substrate is removed from the support substrate.